• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.63.2-63.2
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• 2010

Solar radiation data are used in several forms and for a variety of purposes. The most detailed information we have is beam and diffuse solar radiation on a horizontal surface, by hours, which is useful in simulations of solar processes. Daily data are more often available and monthly total solar radiation on horizontal surface can be used in some process design methods. However, as performance is generally not linear with solar radiation, the use of average may lead to serious errors if non-linearities ara not taken into account. It is also possible to reduce radiation data to more manageable forms by statistical methods. The control of the quality of most measurements is relegated to the control of the measuring instruments and measuring processes themselves. An accurate measurement will usually result from the use of a high-quality instrument that has been accurately calibrated and is properly used by a qualified individual.

• Journal of Positioning, Navigation, and Timing
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• 제5권4호
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• pp.213-219
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• 2016

Most existing studies on the wide-area differential global positioning system (WADGPS) employed a grid ionosphere model for error correction in the ionospheric delay. The present study discusses the application of satellite-based ionospheric delay model that provides an error model as a plane function with regard to individual satellites in order to improve accuracy in the WADGPS. The satellite-based ionospheric delay model was developed by Stanford University in the USA. In the present study, the algorithm in the model is applied to the WADGPS system and experimental results using measurements in the Korean Peninsula are presented. Around 1 m horizontal accuracy was exhibited in the existing planar fit grid model but when the satellite-based model was applied, correction performance within 1 m was verified.

• 치과방사선
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• 제3권1호
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• pp.29-34
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• 1973

The study was made on the facial profile of the normal Korean adults using the roentgenographic cephalograms. The subjects ccnsisted of 50 males and 50 females with the normal occlusion. The measurements were made of the facial angles in skeletal pattern and depth, height and the length in the soft tissue profile. The mean and standard deviations from the subjects were calculated and compared with the samples of male and female. The authors have drawn the conclusions as follows: 1. Compared with the angulation in skeletal patterns, there were no differences between both sexes. 2. Individual variations of the lower face were larger than the upper face in most measuring points. 3. Generally, facial heights were lesser than facial depth in sexual differences. 4. Most dimensions of the facial depth, height and length of the male were larger than those of female.

• Journal of Chest Surgery
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• 제28권11호
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• pp.973-976
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• 1995

The assessment method of human body composion by bioelectrical impedance is very simple, safe, rapid and noninvasive. Based on prediction formulas for total body water from bioelectrical impedance, the observed weight loss should be associated with an increase in impedance. However in edematous patients for dialysis, the calculated total body water loss as calculated from impedance were overestimated and significantly higher than the weight loss after dialysis. So determination of impedance were made in 50 edematous patients before, during and after dialysis. Mean weight loss, which was assumed to be only loss of water was 1719$\pm$ 866 gr and mean impedance change was 71.0 $\pm$ 23.0 Ohm under 50kHz. Body weight loss was highly correlated [r>0.81 with the increase in body impedance under variable frequencies[1, 10, 20, 30, 40, 50 kHz . But there were no differences between frequences. In conclusion, clinical application of bioelectrical impedance method is useful for individual edematous patients with new correlation equation[Y=230+26.8X, X;Impedance change, Y;Calculated total body water loss .

• 한국생활과학회지
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• 제14권3호
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• pp.467-473
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• 2005

The integrative Internet program was developed for the selection of optimal brassiere components according to the breast types of middle-aged women. In this program, a customer is classified into a certain group through three steps of a discriminant analysis. Three variables used in the analysis include breast volume, radii of curvature of under-breast curve, and a distance between inner breast points. Using individual data of three variables, the optimal brassiere components, i.e. brassiere cup size, curvature of front panel and wire, distance between cups, are suggested for each customer. Discrimination of breast types using only 2D measurements is also included for those who do not have easy access to a 3D measurement device.

• 품질경영학회지
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• 제22권1호
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• pp.82-95
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• 1994

When independent individual measurements are taken both $S/c_4$ and $\bar{R}/d_2$ are unbiased estimators of the process standard deviation. However, with dependent data $\bar{R}/d_2$ is not an unbiased estimator of the process standard deviation. On the other hand $S/c_4$ is an asymptotic unbiased estimator. If there exists correlation in the data, positive(negative) correlation tends to increase(decrease) the ARL. The effect of using $\bar{R}/d_2$ is greater than $S/c_4$ if the assumption of independence is invalid. Supplementary runs rule shortens the ARL of X control charts dramatically in the presence of correlation in the data.

• The Journal of the Acoustical Society of Korea
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• 제16권2E호
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• pp.62-69
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• 1997

The effect of pitch on tone durations was studied in several poeces of music. In previous work it was found that higher pitched sounds, of a given duration, were perceived to be of longer duration. That work however, was not undertaken in a musical context. The present work was done to determine whether the previously observed trend was also apparent in musical performances. Several measurements were undertaken. One of these involved analysing the recorded performance duration of notes in several performances of the Mozart Flute Quartet in A-mojor, K.298. Performed durations were also obtained from a Bach Flute Sonata and a Brahms Clarinet Quintet. An analysis of the musical performances revealed that while there were individual differences and exceptions in notes, the musicians tended to play higher notes significantly shortened.

• 한국경영과학회지
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• 제26권1호
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• pp.109-116
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• 2001

The detection of corporate failures is a subject that has been particularly amenable to cross-sectional financial ratio analysis. In most of firms, however, the financial data are available over past years. Because of this, a model utilizing these longitudinal data could provide useful information on the prediction of bankruptcy. To correctly reflect the longitudinal and firm-specific data, the generalized linear model with assuming the first order AR(autoregressive) process is proposed. The method is motivated by the clinical research that several characteristics are measured repeatedly from individual over the time. The model is compared with several other predictive models to evaluate the performance. By using the financial data from manufacturing corporations in the Korea Stock Exchange (KSE) list, we will discuss some experiences learned from the procedure of sampling scheme, variable transformation, imputation, variable selection, and model evaluation. Finally, implications of the model with repeated measurement and future direction of research will be discussed.

• 한국생활과학회지
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• 제12권5호
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• pp.767-776
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• 2003

The purpose of this study was to classify side somatotypes of the trunk by analysing photographic data. Then their distribution according to the age groups was studied. The subjects were 315 females of 18 to 49 year-old. Thirty one photographic measurements were taken to each subject. The factors affecting the side somatotype of the trunk were obtained by principal component analysis, vertical size, posterior/anterior depth and neck posture. The side somatotypes of the trunk were classified into 4 types and their differences were shown by analysing photographic data. The side silhouettes of 4 types were compared with balanced type. By suggesting the canonical discriminant function with the unstandardized canonical coefficient, individual somatotype of the trunk could be discriminated from the photographic data of anterior neck height, anterior waist height, posterior waist depth, buttock height, and anterior depth at the level of back protrusion. The frequency distribution of the side somatotypes of the trunk according to the age groups could be applied for clothing construction and the rate of clothing production.

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.641-646
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• 2003

An accurate and efficient method for measuring the mass of hairy roots using conductometry is established. A conductivity equation expressed in terms of the concentration of the ion species in the medium is suggested. By using this equation, the effect of the individual ions on the total conductivity can be quantitatively analyzed. An equation for the in situ estimation of the cell growth coefficient for determining the mass of hairy roots is established based on measurements of the nitrogen concentration and conductivity during cultivation. The proposed equation does not require preliminary experiments to determine the cell growth coefficient. Instead, the physiological characteristics of the plant species are reflected by introducing the cellular nitrogen content. Since the cell growth coefficient is determined by measuring the major ionic nutrient concentrations, it is more effective to express the dynamics of an actual culture system. This improved method for determining the mass of hairy roots was successfully utilized in a fed-batch culture system.